Electropneumatic action for the operation and control of musical instruments



Sept. '15, 1931. R. ADAMS ET AL ELECTROPNEUMATIC ACTION FOR THE OPERATION AND CONTROL OF MUSICAL INSTRUMENTS Filed Feb.

III/AI mvauroas Edgar 1 21 .Jldanm m' ll. 1? We-6e1- DOngYZd' J1. smith ATTORNEYS Patented Sept. 15, 1 931 UNITED STATES PATENT OFFICE EDGAR RALPH ADAMS, OF EDWARDSTOWN, AND VICTOR ALBERT HENRY \VEBER AND DONALD HUGH SMITH, 0F HENLEY BEACH, AUSTRALIA ELECTROPNEUMATIC ACTION FOR THE OPERATION AND GGNTROL QF MUSICAL INSTRUMENTS Application filed February 6, 1930, Serial No. 426,359, and in Australia May 21, 1929.

being'formed by a flexible diaphragm adapted to normally seal the pipe of the instrument, the bottom of the chamber having air inlet and air outlet holes the former connecting with a trunking containing air under higher pressure than that within the wind chest, and the latter connecting with the atmosphere. Supported upon the bottom of the chamber is a rocking plate valve the two wings of which are adapted to cover the air inlet hole and the air outlet hole respectively; and fitted to the bottom of the chamber adjacent to the air inlet hole therein is an electro magnet such that when the magnet is energized the valve is rocked to close such air inlet and open the air outlet.

In order that our invention may be the more clearly understood We will describe the same with reference to the accompanying drawings in which Fig. 1 is a central section showing our invention applied to the pipe of an organ, and

Fig. 2 is a plan of the parts below line 22 of Fig. 1.

In the drawings we have shown our chamber as formed in the bottom board of the wind chest, that being a simple and convenient manner of forming same, but it may be made as a self-contained unit positioned and secured either within or even outside of the wind chest.

In applying our invention as shown in the drawings we make use of a rocking valve 1 consisting of a plate or disc of soft sheet iron which is bent slightly along its centre to form two wings as shown. This valve is placed on the upper surface of a horizontal plate 2 so that it may rock through a small angle, being held in place by two pins 3 which project from the plate 2 and pass through perforations in the valve. "he rocking valve 1 is faced with leather or other more or less resili nt material to facilitate its operation and to make it air tight and silent in action.

The plate 2 is secured to the wind chest l below a hole or chamber 5 cut in the bottom board of same, and forms the bottom of such chamber. In its one position of rest (its normal position) the valve covers and seals an air outlet hole 6 in the plate 2, and in its other position of rest it covers and seals an air inlet hole 7 in the plate 2.

The air inlet hole 7 communicates through a tube 8 with a trunking 9 containing air from the bellows or blower at a higher pressure than that within the wind chest, and the outlet hole 6 communicates with the atmosphere.

Near the air inlet hole 7 and on the same side of the axis about which the valve 1 rocks is an electro magnet 10, preferably a horseshoe magnet, the poles 01 which protrude into and are held in the bottom plate 2.

The top of the chamber 5 is sealed by a flexible diaphragm 12 of leather or other suitable material, which diaphragm seals the chamber 5 from the wind chest 4 and prevents any passage of air from the one to the other.

Immediately above the diaphragm 12 is a tube 13 of fibre or other suitable material one end of which is situated acent to the diaphragm and is normally sealed thereby, and the other end of which projects into and is secured in a hole in the upper board of the wind chest 4, which hole forms the seat for the foot of the pipe lei or instrument to be operated.

The operation of our invention is as follows:

By means of bellows or blower an air pressure sufficient to operate the pipes of the instrument is maintained in the wind chest 4,

and a substantially higher pressure is maintained in the trunking 9. hen the parts are in the position shown in full lines in Fig. 1, WlllCh lS their normal position, the

high air,pressure-innthe trunking 9 flows" throughgthe' tube 8 and inlet holes?) :into.

the chamber 5 deflecting the diaphragm 12 upward to seal the tube 13 and so prevent any-flow ofair from the -vi-nd chest 4;

through the tube 13 to-the pipe l i hen the electromagnet 10 becomes energized by current controlled from the key:

board the rocking valve 1 is deflected to the position shown byllongiand short dots in Fig. l sealing the inlet hole 7 and therebyv cutting-oil the supply 0t air; fromythe to thelchamber-o, and at the:

trunking 1,9 sametnnequnsealing the outlethole-fi and t i reby permitting the :am

This causesithe- -.diaphnag1n 1211 0 be deflected doWmva-rdby the pressureiiirthe Wind chest 4, such position being shown by long and short; dots in 1Fig. l. The trbe 13 conse guently becomes unsealed and air Iroin the .xvind cheste: 1S admittedato the pipe 14 1 his COIICllillOIl'llOlClSflVlIllQ theelectric cir pressure in the- ;phamber; 5 to, fall to, atmospheric"pressure;

ment mounted in saidrwind chest and hav 7 mg the horn portion-the'reof*d1sposed c'lese 1y adjacent said chamber,=-a high pressure air conduit carried by said Wind chest, a conduitconnecthig said chambe'rand said high pressure conduit and forming an air inlet for said chamber, aniair outlet formed in saidrchamber, an angularly formed me- .tallic; plate valve rockably -supported.be+ tweensaid, inlet and outlet, a flexible .dia-a ingzengagement Wlbll the horn ot said instru:- upon aenergization of said elect-ro-magneta cent; the air inlet of said chamber, whereby said valve Will be rocked to close said inletn-i and open said outlet of said chamber: .1.

chamber and adapted; .to bea-flered into seal-i phnagmsealing ;the uppen portion ofsaid merit; and an electromagnetdisposed adja ln-testimonythatsweclaimEthe foregoing as our vinvention We have signeid'our names cuit remains closed. When the eiectromag,

netcircuit. is opened by. releasing the key ;-contact=-therocking: valve 1 reverts to 1ts e ie: higher airnormal: position allowingpressure ironr-the trunking 9 to fill the chalmbeiweand so deflect the diaphragm 12 upwardsfsealing the openingto the tube 13 iand cutting ofi the supply of air fromthe winchchestto theI-pipeor musical-instrument- ,Whichthenceases :to: operate.-

The same device; or mechanism may 'be used to control the supplyiof air underpres- ;sureto a pneumatic motor of any ordinary type which may beeused to operate contacts orother functions.- 'KVllGlQ a mechanical force;

is .required.- i The air tube to t-hemotor then takes-theplace oi the pipe to be played.

What We claim is V 1. .An improved electropneuma-tic action for the. operation andcontrol of musical in-- striunents conipnising a chamber positioned} in'the lower part of the Windchesh-and adacent to the foot of the .pipe of the instrument or of ti e pneumatic inoto'rroi device-- toebe' operatech th'e top ofthe'chamber being formed by a flexible diaphragm' adapted to sea-la tube communicatingnvith. the saidw- .-,p1pe,and: thekbottomiofthe chamber hav 1ng1 air :1nlet and; air outlet holes; the former connecting with 1a trunking :containing. air

under higher-pressure than that within the: wind; chest and the latter connecting avith :the atmosphere, a rocking plate valve snipe;

ported upon the bottom of the chamber, and

an electromagnet fitted'to the bottom of thew.

chamber adjacent to; the air inlet hole there;-

this -thtday ofJanuary, 1930.

' VEDGARRALPHIADAMSU JICTGR 'ALBERT HENRY WEBER. 1

DONALD Hues smnn.

in and adapteduto" be energized flODlQtllB'J.

65mkeyboard or manual.iso that Whenthennag-w 

